feat: Add `.artifacts` to .NET template

[hyperupcall]

Pull Request

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New or update

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New

• [ ] Template - New .gitignore template
• [ ] Composition - Template made from smaller templates
• [ ] Inheritance - Template similar to an existing template
• [] Patch - Template extending functionality of existing template

Update

• [x] Template - Update existing .gitignore template

Details

As mentioned in https://github.com/toptal/gitignore.io/issues/616, this updates the .NET gitignore template to account for the changes in output path

Fixes https://github.com/toptal/gitignore.io/issues/616